Electric heating-pad.



s. ELEOTRIO HEATING PAD. I APPLIOATION FILED SEPT; 25, 1910.

Patented Jan. 30, 1912.

fiYI IEZSZTUH I/J/ALLACE' 5? 52,422. 5

His firroazswx EUN ITED strATns rA rEnT OFFICE.

WALLACE S. CLARK, F SCHENEC'IADY, NEW YORK, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION QF NEW YORK.

ELECTRIC HEATING-PAD.

. I l I 1,015,991. 'Srwficatwn 0! Letters ratent. Patented'J an. 30, 1912.

Application filed September as, 19x0. Serial No. 584.222.

To all whomit may concern: wires at the projection 12. The two Be it known that I, Warn-ion S. CLARK, a sheets of rubber, with the windings between citizen of the United States, residing at l them, may be secured together in any de- Schenectady,-in the county ot' Schenectady, sired way, as, for instance, by placing the, State of New York, have invented certain windings between the two sheets applying new and useful Improvements in Electric i suitable pressure and then vulcanizing tie Heating-Pads, of which the following is a 'gtwo sheets together in a well-known manner. specification. lhe resulting product is practically a single 6 This invention relates to electric heaters 1 sheet of rubber with a resistance conductor L0' and has for its object the provision of a sixnembedded centrally therein. The conductor ple and efiicicnt device of this character in i is firmly anchored in place so that the parts which the heating element 'is. concealed cannot short circuit on each other or become within a body of flexible insulating material. i exposed. Furthermore, the rubber forms a My invention relates more specifically to practically airand water-tight casing around 15 heating devices, such as electric heating pads the conductor which is desirable for obvlous and the like. These devices, as ordinarily reasons. It will be seen that I have proconstructed, are thin 'flexible bodies having I vided a heating pad which when operated a resistance conductor within them and have within proper temperature linjits will be been made in various ways, as for instance, practically indestructible.

2 by sewing or otherwise attaching theresist- It is quite obvious that various modifi- 'ance conductor to a body of insulating cations .of my invention will suggest themfabric. selves to those skilled in the art without de- In carrying out my invention, I embed parting from the spirit of my invention, the the resistance conductor within a body of scope of which is setforth in the annexe 5215' water-Epcot flexible insulating material, such i claims.

v 50 absolutely necessary. In this -case, ,I have Witnesses:

as rub r or the'lik'e, so that the conductor I What I claim as new and desire to secure will be firmly anchored in place and will be i by Letters Patent of the United States is 'unafiected by moisture. i 1. An electric heater comprising a resist- In the accompanying drawings in which ance conductor embedded in a body of flexi- 30 IV have shownmy invention embodied in l ble water proof insulating material.

--concrete*" form for purposes,ofillustration, 2. An electric heater conprising a resist- -Figure 1 represents a plan view of one form ance conductor embeddedin a body of flexiof my device and Fig. 2 is an. end view of ble rubber. the .same. v y An electric heater comprising two 35 Referring to'the drawings, 10 and 11 are sheets of flexible rubber secured together two sheets of rubber, which I have shown 1 with a resistance conductor embedded befor purposes of illustration as circular in ttween them. I

form having projecting portions 12, as .4. An electric heater comprising a resist- 7 shown. Between these two sheets of rubber ance conductor embedded between two'sheets 40 I secure the resistance conductor 13. This 1 of rubber which are vulcanized together.

conductor may, of course, be arranged in 1 5. Anelectric heater comprising a supany desired manner, and may have a thin i port, a resistance conductor wound thereon, covering of insulation if desired. For purand two sheets of rubber one on each side poses of illustration I have shown the conof the support vulcanized together so as 45 duetor wound in the form of concentric to entirely inclose the support.

rings. These may consist of wire wound In witness whereof, I have hereunto set spirally around thin rings of insulation 14, my hand this 26th day of September, 1910. such as mica or the like, although it is ob- I WALLACE CLARK vious that such a support for the wire is not I,

shown three of these windings in ring form BENJAMIN HULL, rranged so as to connect with the lead HELEN Quronn. 

